1. Field of the Invention
The present invention relates to optical waveguides, and more particularly, the present invention relates to ferrules for optical waveguides.
2. Description of the Related Art
The increasing demand for high-speed voice and data communications has led to an increased reliance on optical communications, particularly optical fiber communications. The use of optical signals as a vehicle to carry channeled information at high speeds is preferred in many instances to carrying channeled information at other electromagnetic wavelengths/frequencies in media such as microwave transmission lines, co-axial cable lines and twisted pair transmission lines. Advantages of optical media are, among others, high-channel (bandwidth), greater immunity to electromagnetic interference, and lower propagation loss. In fact, it is common for high-speed optical communication system to have signal rates in the range of approximately several Giga bits per second (Gbit/sec) to approximately several tens of Gbit/sec.
The optical fiber ferrule is a commonly utilized component in optical fiber connectors and other optical network devices, and FIG. 1 is a cross-sectional view of a conventional optical fiber ferrule. In such a component, a fiber carrier 101 made of glass extends longitudinally within a carrier tube 102 also made of glass. As shown, the fiber carrier 101 includes a precisely dimensioned through-hole 103 which contains an optical fiber 104. However, the conventional configuration of FIG. 1 suffers certain drawbacks. For example, the fiber 104 must be threaded into the glass carrier tube 102, which is a difficult and sometimes costly process. Also, the carrier tubes 102 are drawn from a heated preform which makes the fabrication thereof relatively expensive.
According to one aspect of the present invention, an optical waveguide ferrule includes a carrier tube, a waveguide carrier located within the carrier tube, and an optical waveguide extending lengthwise in a longitudinal direction within the waveguide carrier. The waveguide carrier is made up of a first carrier body having a first principal surface and a second carrier body having a second principal surface which confronts the first principal surface. The first principal surface has a first groove which extends lengthwise in the longitudinal direction, and the second principal surface has a second groove which extends lengthwise in the longitudinal direction. The first and second grooves are aligned with one another to define an elongate cavity which extends lengthwise in the longitudinal direction, and the optical waveguide is contained within the elongate cavity.
According to another aspect of the invention, an optical waveguide ferrule includes a carrier tube, a plurality of waveguide carriers located within the carrier tube, and a plurality of optical waveguides extending lengthwise in a longitudinal direction within the waveguide carrier. The waveguide carrier is made up of a first carrier body having a first principal surface and a second carrier body having a second principal surface which confronts the first principal surface. The first principal surface has a plurality of first grooves which extend lengthwise in the longitudinal direction, and the second principal surface has a plurality of second grooves which extend lengthwise in the longitudinal direction. The plurality of first grooves are aligned with the plurality of second grooves to define a plurality of elongate cavities which extend lengthwise in the longitudinal direction, and the plurality of optical waveguides are contained within the plurality of elongate cavities, respectively.
According to still another aspect of the present invention, a silicon wafer is etched to form a plurality of grooves which extend parallel to one another in a first surface of the silicon wafer. The silicon wafer further etched to form a plurality of trenches in a second surface of the silicon wafer which is opposite the first surface. In particular, the trenches are formed so as to extend parallel to one another between respectively adjacent pairs of the parallel grooves and in a same direction as the parallel grooves. The silicon wafer is separated into discrete chips at respective bottoms of the trenches such that the first surface of each of the discrete chips includes at least one of the grooves. An optical waveguide is placed in a groove of a first one of the discrete chips, and the first surface of a second one of the discrete chips is placed against the first surface of the first one of the discrete chips such that the groove of the first one of the discrete chips is aligned with a groove of the second one of the discrete chips. As such, the optical waveguide is enclosed between the respective grooves of the first and second discrete chips.
According to yet another aspect of the present invention, a silicon wafer is etched to form a plurality of grooves which extend parallel to one another in a first surface of the silicon wafer. The silicon wafer is further etched to form a plurality of trenches in the first surface of the silicon wafer. In particular, the trenches are formed so as to extend parallel to one another between respectively adjacent pairs of the parallel grooves and in a same direction as the parallel grooves. The silicon wafer is separated into discrete chips at respective bottoms of the trenches such that the first surface of each of the discrete chips includes at least one of the grooves. An optical waveguide is placed in a groove of a first one of the discrete chips, and the first surface of a second one of the discrete chips is placed against the first surface of the first one of the discrete chips such that the groove of the first one of the discrete chips is aligned with a groove of the second one of the discrete chips. As such, the optical waveguide is enclosed between the respective grooves of the first and second discrete chips.